All tech logs of script are cut up to X lines CJ Settings

What's difference between 'em ? Old Backup is for back-compatibility only so basically you wont need, I use it to transfer trades from very very old versions of SmartCJ.

Mysql Backup is actually a regular mysqldump.

If case of DB error script tries to recover automatically. If it's impossible - you can try to do it manually. I've never used this option :)

Logs access to admin area.

Reset all stats. Notice it doesnt delete traders, reset stats.